Residency and movement patterns of juvenile yellowfin bream Acanthopagrus australis, stocked on estuarine artificial reefs

Context. Successful fish stocking relies upon releasing cohorts directly into habitat containing suitable supporting resources. To facilitate this, an emerging trend has seen fish released onto artificial reefs. 

Aims. We compared the residency and movement patterns of juvenile sparids (yellowfin bream – Acanthopagrus australis), stocked on artificial reefs and natural habitat, to determine the suitability of incorporating artificial structures as release sites in future stocking programs. 

Methods. Forty hatchery-reared yellowfin bream were evenly divided and stocked on either artificial reef or natural habitat within an east-Australian estuary, and tracked using acoustic telemetry. 

Key results. Artificial reefs provided greater habitat complexity than the natural habitat and fish stocked onto these structures showed greater fidelity to their release site and were detected for longer periods of time than those stocked into less complex natural habitat. 

Conclusions. The high residency levels of fish around artificial reef sites indicate they contain resources to support stocked juvenile sparids. 

Implications. Stocked yellowfin bream can tolerate a range of salinity and temperatures, allowing flexibility in stocking programs. Future stocking of bream or other sparids should consider releasing fish onto artificial reefs where available. Additionally, the deployment of reefs could aid existing stocking programs.